Dystonia-Parkinson syndrome: differential effects of levodopa and dopamine agonists.

Eleven patients who presented with predystonic syndrome later developed pure dystonic syndromes and later developed parkinsonism. This suggests that dystonic syndromes can be the precursor to a mixed syndrome including both dystonia and parkinsonism. While the parkinsonian features in such patients respond to either levodopa or direct-acting agonists, levodopa often exacerbates the underlying dystonia. Direct acting agonists appear to be less liable to do this.